Technology for rapidly retrieving and presenting information according to content of a video or speech and the like is very useful in many kinds of situations. For example, if a system for sequentially presenting related material matching the course of proceedings during a meeting, or a system for automatically obtaining information related to content of inquiries to a telephone call center can be realized, a user can focus on the meeting or response itself, and productivity is improved.
An example of a conventional system for performing information retrieval based on speech in this way is disclosed in Patent Document 1.
As shown in FIG. 5, this conventional information retrieval system is configured from a speech input means, a speech recognition means, an action data storage means in which a keyword and an action corresponding thereto are stored, a keyword extraction means for extracting a keyword registered in advance from speech recognition result text, an action data condition judging means for judging whether or not the extracted keyword satisfies any action data condition, and an action execution means for executing an action when a condition is established (furthermore, the action data condition judging means and the action execution means of FIG. 5 correspond to an “information presentation processing means” in Patent Document 1).
The conventional information retrieval system having this type of configuration operates as follows. Specifically, a speech signal received from a speech input unit is converted to text by the speech recognition means. A keyword registered in advance is extracted from the converted text. Finally, a judgment is made as to whether or not the extracted keyword satisfies a condition for execution of an action that has been designed in advance, and if the judgment result is true, a prescribed action is executed. A principal action is to display text that has been determined in advance.
In addition, taking into view an information retrieval system according to input text, not speech, similar text retrieval technology for performing retrieval according to the degree of similarity of the input text, not depending on a keyword, is known.
[Patent Document 1]
JP Patent Kokai Publication No. JP-P2005-215726A
[Non-Patent Document 1]
Nakamura, et al., Analysis of Acoustic and Linguistic Features of Spoken Word Speech, The Institute of Electronics, Information and Communication Engineers, Technical Report, SP2006-4 (2006-5).